Rize’s crimson eyes—he noted them absently, thinking them colored contacts—gleamed with interest. “A room. I like that. You’re strange, Kaneki-kun.”
Driven by a mix of shyness and a desire to talk about books, Kaneki arranges a date with the woman, . However, the date ends in a dark alleyway where Rize reveals her true nature as a Ghoul known as the "Binge Eater." She attacks Kaneki, intending to devour him. Just as she crushes him with her Kagune (predatory organ), steel beams fall from a construction site above, critically injuring both of them.
“My name is Uta,” the white-haired man said. “That was quite a show. But you won’t survive long on rats. And the alternative… well, you seem like the type who’d rather die than hurt a person.” tokyo ghoul season 1 ep 1
It came not as a bite, but as a catastrophic crash. A deafening screech of twisting metal, a shower of sparks, and a geyser of crimson that wasn't his own. Rize’s scream was cut short. The tentacles holding him spasmed and went limp. He fell, landing hard on his back, the wind knocked out of him once more.
Days later, Kaneki is approached by a group of ghouls, including Nishiki Nishio and Shuu Tsukiyama, who claim to be his friends. They reveal to him that Rize was a ghoul who had been living among humans and that she had saved his life by transferring her ghoul blood into his body. You’re strange, Kaneki-kun
She tossed him like a ragdoll. He slammed into a pile of iron rebar, the breath knocked out of him. Pain, sharp and white-hot, lanced through his ribs. Before he could gasp, a tentacle wrapped around his ankle and hoisted him into the air, dangling him upside down. His glasses fell, skittering across the concrete. The world became a blur of upside-down streetlights and Rize’s predatory, joyful face.
He ended up in a dark, anonymous park. His stomach screamed. It wasn’t the familiar ache of skipped meals. It was a deep, cellular terror. He was starving to death on a full stomach. A rat scurried near a trash can. In a flash of movement he didn’t consciously control, his hand shot out and caught it. He stared at the squealing creature. The scent of its life, its hot, pumping blood, was the most beautiful thing he had ever smelled. Without thinking, he brought it to his mouth. “My name is Uta,” the white-haired man said
“I… I’m not feeling well,” Kaneki whispered, and fled.
Three days later, he was discharged. He walked home under a gray, weeping sky. The world looked different. Colors were too vivid. Sounds were too loud. And the people… the people smelled like walking banquets. He clutched his stomach, nauseated by his own cravings.
Tragedy strikes when Kaneki and Rize are involved in a traffic accident. Rize is killed, but not before she reveals to Kaneki that she is a ghoul. In a desperate attempt to save Kaneki, she injects her ghoul blood into his body.
This episode sets the stage for the rest of the series, which explores themes of identity, community, and the struggle for acceptance in a world where ghouls are seen as monsters.